Investigation of Argon Plasma Damage on Ultra Low-κ Dielectrics

A porous ultra low-κ dielectric (pULK) and a dense SiCOH dielectric were investigated before and after a plasma treatment with argon in terms of the change in the bonding types, the relative permittivity and the water uptake. Fourier transform infrared (FTIR) spectroscopy revealed a change in the bonding types of the dielectrics in general and a significant increase in the hydroxyl band especially. The high hydroxyl amount leads to an increase in the relative permittivity of these dielectrics by up to 6.25% for SiCOH and up to 12.5% for the pULK material. Furthermore, if water diffuses into the dielectric films from the environment, the moisture uptake is up to 2.7 times higher in saturation at 80% relative humidity in comparison to the untreated samples. Due to the plasma damaged upper layer of the materials, the diffusion process of water into the bulk dielectrics is significant reduced. Overall, it has been found that the pULK material is more vulnerable to the used plasma treatment in comparison to the dense SiCOH film. © 2014 The Electrochemical Society. [DOI: 10.1149/2.0041501jss] All rights reserved.

[1]  P. Ho,et al.  Plasma processing of low-k dielectrics , 2013 .

[2]  N. Possémé,et al.  Impact of low-k structure and porosity on etch processes , 2013 .

[3]  J. W. Bartha,et al.  Fourier Transform Infrared Spectroscopy of Moisturized Low- $\kappa$ Dielectric Materials , 2011, IEEE Transactions on Electron Devices.

[4]  G. Oehrlein,et al.  Mechanistic study of ultralow k-compatible carbon dioxide in situ photoresist ashing processes. I. Process performance and influence on ULK material modification , 2010 .

[5]  Hartmut Ruelke,et al.  Investigation of Moisture Uptake in Low-$\kappa$ Dielectric Materials , 2010, IEEE Transactions on Electron Devices.

[6]  S. Schulz,et al.  Investigation of physical and chemical property changes of ultra low-κ SiOCH in aspect of cleaning and chemical repair processes , 2010 .

[7]  Willi Volksen,et al.  Low dielectric constant materials. , 2010, Chemical reviews.

[8]  Denis Shamiryan,et al.  Effect of Porogen Residue on Chemical, Optical, and Mechanical Properties of CVD SiCOH Low-k Materials , 2009 .

[9]  M. Bersani,et al.  On the photoresist stripping and damage of ultralow k dielectric materials using remote H2- and D2-based discharges , 2007 .

[10]  P. Ho,et al.  Mechanistic Study of Plasma Damage and CH4 Recovery of Low k Dielectric Surface , 2007, 2007 IEEE International Interconnect Technology Conferencee.

[11]  P. Ho,et al.  Effect of CH4 plasma treatment on O2 plasma ashed organosilicate low-k dielectrics , 2007 .

[12]  G. Mannaert,et al.  Low dielectric constant materials: challenges of plasma damage , 2006, 2006 8th International Conference on Solid-State and Integrated Circuit Technology Proceedings.

[13]  C. K. Inoki,et al.  Damage of ultralow k materials during photoresist mask stripping process , 2006 .

[14]  A. Grill,et al.  The Effect of Plasma Chemistry on the Damage Induced to Porous SiCOH Dielectrics , 2006 .

[15]  V. Rouessac,et al.  Precursor chemistry for ULK CVD , 2005 .

[16]  N. Possémé,et al.  Etching of porous SiOCH materials in fluorocarbon-based plasmas , 2004 .

[17]  Karen Maex,et al.  Low-k dielectric materials , 2004 .

[18]  A. Grill,et al.  Structure of low dielectric constant to extreme low dielectric constant SiCOH films: Fourier transform infrared spectroscopy characterization , 2003 .

[19]  Karen Maex,et al.  Low dielectric constant materials for microelectronics , 2003 .

[20]  M. S. Hwang,et al.  Infrared spectroscopy study of low-dielectric-constant fluorine-incorporated and carbon-incorporated silicon oxide films , 2001 .

[21]  Paul S. Ho,et al.  Low Dielectric Constant Materials for ULSI Interconnects , 2000 .

[22]  D. Tallant,et al.  Surface structure and chemistry of high surface area silica gels , 1990 .

[23]  J. K. Srivastava,et al.  Low‐temperature growth of silicon dioxide films: A study of chemical bonding by ellipsometry and infrared spectroscopy , 1987 .